<head th:fragment="header">
    <!-- 必要的标签 -->
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
    <!-- Bootstrap CSS -->
    <link crossorigin="anonymous" integrity="sha512-6KY5s6UI5J7SVYuZB4S/CZMyPylqyyNZco376NM2Z8Sb8OxEdp02e1jkKk/wZxIEmjQ6DRCEBhni+gpr9c4tvA==" href="https://lib.baomitu.com/twitter-bootstrap/5.1.1/css/bootstrap.min.css" rel="stylesheet">
    <link rel="stylesheet" th:href="@{/class1.css}">
</head>
<nav th:fragment="navbar" class="navbar navbar-expand-lg navbar-dark bg-dark">
    <div class="container">
        <button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarTogglerDemo03" aria-controls="navbarTogglerDemo03" aria-expanded="false" aria-label="Toggle navigation">
            <span class="navbar-toggler-icon"></span>
        </button>
        <a class="navbar-brand" th:href="@{/classification1}">SpringBoot</a>

        <div class="collapse navbar-collapse w" id="navbarTogglerDemo03">
            <ul class="navbar-nav mr-auto mt-2 mt-lg-0">
                <li class="nav-item active">
                    <a class="nav-link" th:href="@{/classification1}">主页</a>
                </li>
                <li class="nav-item">
                <a class="nav-link" th:href="@{comments/new}">留言</a>
                </li>
                <li class="nav-item">
                    <div class="box">
                    <div><a class="choose" href="#">选择</a></div>
                    <div> <a class="creat" th:href="@{/articles/new}">文章创建</a></div>
                    <div> <a class="warn" th:href="@{/warns/new}">要求</a></div>
                    <div> <a class="attendance" th:href="@{/attendances/new}">签到</a></div>
                    </div>
                </li>
                <li class="nav-item">
                    <div><a class="logout"th:href="@{/logout}">退出登录</a> </div>
                </li>

            </ul>

        </div>
    </div>

</nav>
